Pad conditioner auto disk change

ABSTRACT

A method and apparatus for replacing a polishing pad conditioning disk is a chemical mechanical polishing system is provided. The apparatus comprises a disk load/unload station for unloading used conditioning disks from a pad conditioning assembly and loading unused conditioning disks onto the pad conditioning assembly, on or more disk storage stations for storing both used and unused conditioning disks, and a central robot having a range of motion sufficient for transferring both used an unused conditioning disks between the disk load/unload station and the one or more disk storage stations. Embodiments described herein reduce the length of system interruption by eliminating the need to safety lock out the system for the replacement of polishing pad conditioning disks.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments described herein generally relate to the planarization ofsubstrates. More particularly, the embodiments described herein relateto the conditioning of polishing pads.

2. Description of the Related Art

Sub-quarter micron multi-level metallization is one of the keytechnologies for the next generation of ultra large-scale integration(ULSI). The multilevel interconnects that lie at the heart of thistechnology require planarization of interconnect features formed in highaspect ratio apertures, including contacts, vias, trenches and otherfeatures. Reliable formation of these interconnect features is veryimportant to the success of ULSI and to the continued effort to increasecircuit density and quality on individual substrates and die.

Multilevel interconnects are formed using sequential material depositionand material removal techniques on a substrate surface to form featurestherein. As layers of materials are sequentially deposited and removed,the uppermost surface of the substrate may become non-planar across itssurface and require planarization prior to further processing.Planarization or “polishing” is a process in which material is removedfrom the surface of the substrate to form a generally even, planarsurface. Planarization is useful in removing excess deposited material,removing undesired surface topography, and surface defects, such assurface roughness, agglomerated materials, crystal lattice damage,scratches, and contaminated layers or materials to provide an evensurface for subsequent photolithography and other semiconductormanufacturing processes.

Chemical Mechanical Planarization, or Chemical Mechanical Polishing(CMP), is a common technique used to planarize substrates. CMP utilizesa chemical composition, such as slurries or other fluid medium, forselective removal of materials from substrates. In conventional CMPtechniques, a substrate carrier or polishing head is mounted on acarrier assembly and positioned in contact with a polishing pad in a CMPapparatus. The carrier assembly provides a controllable pressure to thesubstrate, thereby pressing the substrate against the polishing pad. Thepad is moved relative to the substrate by an external driving force. TheCMP apparatus affects polishing or rubbing movements between the surfaceof the substrate and the polishing pad while dispersing a polishingcomposition to affect chemical activities and/or mechanical activitiesand consequential removal of materials from the surface of thesubstrate.

The polishing pad performing this removal of material must have theappropriate mechanical properties for substrate planarization whileminimizing the generation of defects in the substrate during polishing.Such defects may be scratches in the substrate surface caused by raisedareas of the pad or by polishing by-products disposed on the surface ofthe pad, such as accumulation of conductive material removed from thesubstrate precipitating out of the electrolyte solution, abradedportions of the pad, agglomerations of abrasive particles from polishingslurries, and the like. The polishing potential of the polishing padgenerally lessens during polishing due to wear and/or accumulation ofpolishing by-products on the pad surface, resulting in sub-optimumpolishing qualities. This sub-optimization of the polishing pad mayoccur in a non-uniform or localized pattern across the pad surface,which may promote uneven planarization of the conductive material. Thus,the pad surface must periodically be refreshed, or conditioned, torestore the polishing performance of the pad.

Therefore, there is a need for improved methods and apparatus forconditioning polishing pads.

SUMMARY OF THE INVENTION

Embodiments described herein generally relate to the planarization ofsubstrates. More particularly, the embodiments described herein relateto the conditioning of polishing pads. In one embodiment an apparatusfor replacing a polishing pad conditioning disk is a chemical mechanicalpolishing system is provided. The apparatus comprises a disk load/unloadstation for unloading used conditioning disks from a pad conditioningassembly and loading unused conditioning disks onto the pad conditioningassembly, one or more disk storage stations for storing both used andunused conditioning disks, and a central robot having a range of motionsufficient for transferring both used an unused conditioning disksbetween the disk load/unload station and the one or more disk storagestations.

In another embodiment a system for chemical mechanical polishing of asubstrate is provided. The system comprises a platen assembly, apolishing surface supported on the platen assembly, one or morepolishing heads on which substrates are retained while polishing, a padconditioning assembly for dressing the polishing surface by removingpolishing surface by removing polishing debris and opening the pores ofthe polishing surface, and an auto disk changer module for replacing apolishing pad conditioning disk.

In yet another embodiment a method for replacing a polishing padconditioning disk in a chemical mechanical polishing system is provided.The method comprises unloading a used conditioning disk from a padconditioning assembly at a disk load/unload station, retrieving the usedconditioning disk with a central robot, transferring the usedconditioning disk using the central robot from the disk load/unloadstation to one or more disk storage stations, unloading the usedconditioning disk, retrieving an unused conditioning disk from the oneor more disk storage stations, transferring the unused conditioning diskusing the central robot to the load/unload station, and loading theunused conditioning disk onto the pad conditioning assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentinvention can be understood in detail, a more particular description ofthe invention, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate onlytypical embodiments of this invention and are therefore not to beconsidered limiting of its scope, for the invention may admit to otherequally effective embodiments.

FIG. 1 is a is a top plan view of one embodiment of a chemicalmechanical polishing system;

FIG. 2 is a partial perspective view of a polishing station of FIG. 1;

FIG. 3 is a top schematic view of the auto disk changer module of FIG.2;

FIG. 4 is a side schematic view of a disk load/unload pedestal;

FIG. 5 is a top schematic view of another embodiment of an auto diskchanger module;

FIG. 6 is a top schematic view of another embodiment of an auto diskchanger module;

FIG. 7 is a top schematic view of another embodiment of a polishingstation of a chemical mechanical polishing system; and

FIG. 8 is a side view of one embodiment of a pad conditioning assembly.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. It is contemplated that elements disclosed in oneembodiment may be beneficially utilized on other embodiment withoutspecific recitation.

DETAILED DESCRIPTION

Embodiments described herein generally relate to the planarization ofsubstrates. More particularly, the embodiments described herein relateto the conditioning of polishing pads. A conventional pad conditioningapparatus places an abrasive material in contact with a moving polishingpad. For example, a pad conditioning disk may be used to scrape andabrade the pad surface, and to expand and re-roughen the pad. The padconditioning disk may be coupled with a rotatable backing element.

Replacement of pad conditioning disks is a time consuming process thatreduces system availability. Currently, the pad conditioning disk ismanually replaced about every 15 to 30 hours. The existing manualreplacement process requires safety lock out and tag out of the systemso the operator can physically enter the processing environment.Embodiments described herein will greatly extend the time requiredbetween operator intervention with the system. Embodiments describedherein automate the conditioning disk replacement process, reducing thelength of system interruption by eliminating the need to safety lock outthe system for the manual conditioning disk change. Embodimentsdescribed herein also enable the use of different types of conditioningdisks during the polishing process. For example, an aggressive diamondconditioning disk may be used for pad break-in, a less aggressivediamond conditioning disk may be used for pad conditioning, and a brushdisk for pad cleaning.

In one embodiment, the pad conditioning arm discards a used conditioningdisk at one location and retrieves an unused conditioning disk fromanother location. In one embodiment, the locations each comprise aconditioning disk holder which holds a vertical stack of conditioningdisks. In another embodiment, the unused disk stack may be locatedvertically above the old disk stack, reducing the system footprint. Inone embodiment, the conditioning disk may be coupled with and decoupledfrom the pad conditioning arm by actuators located on the padconditioning arm or actuators located on the disk stack. In anotherembodiment, coupling and decoupling of the conditioning disk from thepad conditioning arm may be accomplished by passive mechanisms takingadvantage of the existing up and down motion of the pad conditioningarm.

In another embodiment, the auto conditioning disk change may beaccomplished by carrying spare conditioning disks on the padconditioning arm. In one embodiment, the pad conditioning arm may indexbetween pad conditioning disks to extend the useable life of eachconditioning disk. For example, the spare conditioning disks may beraised above the platen and not used until the active conditioning diskreaches the end of its life. Alternatively, the multiple conditioningdisks may be cycled in and out at high frequency to average outvariations in conditioning disk quality.

While the particular apparatus in which the embodiments described hereincan be practiced is not limited, it is particularly beneficial topractice the embodiments in a REFLEXION Lk CMP system and MIRRA MESA®system sold by Applied Materials, Inc., Santa Clara, Calif.Additionally, CMP systems available from other manufacturers may alsobenefit from embodiments described herein. Embodiments described hereinmay also be practiced on overhead circular track polishing systemsincluding the overhead circular track polishing systems described inU.S. Provisional Patent Application No. 61/043,582 (Attorney Docket No.013036L), titled CIRCULAR TRACK POLISHING SYSTEM ARCHITECTURE and U.S.Provisional Patent Application No. 61/043,600 (Attorney Docket No.013194L), titled POLISHING HEAD FOR A TRACK SYSTEM both of which arehereby incorporated by reference in their entirety.

FIG. 1 is a top plan view illustrating one embodiment of a chemicalmechanical polishing (“CMP”) system 100 comprising an auto disk changermodule 150 for automatic replacement of pad conditioning disks. The CMPsystem 100 includes a factory interface 102, a cleaner 104 and apolishing module 106. A wet robot 108 is provided to transfer substrates170 between the factory interface 102 and the polishing module 106. Thewet robot 108 may also be configured to transfer substrates between thepolishing module 106 and the cleaner 104. The factory interface 102includes a dry robot 110 which is configured to transfer substrates 170between one or more cassettes 114 and one or more transfer platforms116. In one embodiment depicted in FIG. 1, four substrate storagecassettes 114 are shown. The dry robot 110 has sufficient range ofmotion to facilitate transfer between the four cassettes 114 and the oneor more transfer platforms 116. Optionally, the dry robot 110 may bemounted on a rail or track 112 to position the robot 110 laterallywithin the factory interface 102, thereby increasing the range of motionof the dry robot 110 without requiring large or complex robot linkages.The dry robot 110 additionally is configured to receive substrates fromthe cleaner 104 and return the clean polished substrates to thesubstrate storage cassettes 114. Although one substrate transferplatform 116 is shown in the embodiment depicted in FIG. 1, two or moresubstrate transfer platforms may be provided so that at least twosubstrates may be queued for transfer to the polishing module 106 by thewet robot 108 at the same time.

Still referring to FIG. 1, the polishing module 106 includes a pluralityof polishing stations 124 on which substrates are polished whileretained in one or more polishing heads 126. The polishing stations 124are sized to interface with two or more polishing heads 126simultaneously so that polishing of two or more substrates may occurusing a single polishing station 124 at the same time. The polishingheads 126 are coupled to a carriage (not shown) that is mounted to anoverhead track 128 that is shown in phantom in FIG. 1. The overheadtrack 128 allows the carriage to be selectively positioned around thepolishing module 106 which facilitates positioning of the polishingheads 126 selectively over the polishing stations 124 and load cup 122.In the embodiment depicted in FIG. 1, the overhead track 128 has acircular configuration which allows the carriages retaining thepolishing heads 126 to be selectively and independently rotated overand/or clear of the load cups 122 and the polishing stations 124. Theoverhead track 128 may have other configurations including elliptical,oval, linear or other suitable orientation and the movement of thepolishing heads 126 may be facilitated using other suitable devices.

In one embodiment depicted in FIG. 1, two polishing stations 124 areshown located in opposite corners of the polishing module 106. At leastone load cup 122 is in the corner of the polishing module 106 betweenthe polishing stations 124 closest the wet robot 108. The load cup 122facilitates transfer between the wet robot 108 and the polishing head126. Optionally, a third polishing station 124 (shown in phantom) may bepositioned in the corner of the polishing station 124 opposite the loadcups 122. Alternatively, a second pair of load cups 122 (also shown inphantom) may be located in the corner of the polishing module 106opposite the load cups 122 that are positioned proximate the wet robot.Additional polishing stations 124 may be integrated in the polishingmodule 106 in systems having a larger footprint.

Each polishing station 124 includes a polishing surface 130 capable ofpolishing at least two substrates at the same time and a matching numberof polishing units for each of the substrates. Each of the polishingunits includes a polishing head 126, a conditioning module 132, apolishing fluid delivery module 134, and an auto disk changer module150. In one embodiment, the conditioning module 132 may comprise a padconditioning assembly 140 which dresses the pad by removing polishingdebris and opening the pores of the pad. In another embodiment, thepolishing fluid delivery module 134 may comprise a slurry delivery arm.In one embodiment, each polishing station 124 comprises multiple padconditioning assemblies 132, 133. In one embodiment, each polishingstation 124 comprises multiple fluid delivery arms 134, 135 for thedelivery of a fluid stream to each polishing stations 124. The polishingsurface 130 is supported on a platen assembly 202 (see FIG. 2) whichrotates the polishing surface 130 during processing. In one embodiment,the polishing surface 130 is suitable for at least one of a chemicalmechanical polishing and/or an electrochemical mechanical polishingprocess. In another embodiment, the platen may be rotated duringpolishing at a rate from about 10 rpm to about 150 rpm, for example,about 50 rpm to about 110 rpm, such as about 80 rpm to about 100 rpm.

Each conditioning module 132 includes a pad conditioning assembly 140.The pad conditioning assembly 140 comprises a conditioning head 142supported by a support assembly 146 with a support arm 144 therebetween.The support assembly 146 is coupled with a base 147 and is adapted toposition the conditioning head 142 in contact with the polishing surface130, and further is adapted to provide a relative motion therebetween.The support arm 144 has a distal end coupled to the conditioning head142 and a proximal end coupled to the base 147. The base 147 rotates tosweep the conditioning head 142 across the polishing surface 130 tocondition the polishing surface 130. The conditioning head 142 is alsoconfigured to provide a controllable pressure or downforce tocontrollably press the conditioning head 142 toward the polishingsurface 130. The downforce pressure can be in a range between about 0.5psi to about 20 psi, for example, between about 1 psi and about 14 psi.The conditioning head 142 generally rotates and/or moves laterally in asweeping motion across the polishing surface 130. In one embodiment, thelateral motion of the conditioning head 142 may be linear or along anarc in a range of about the center of the polishing surface 130 to aboutthe outer edge of the polishing surface 130, such that, in combinationwith the rotation of the platen assembly 202, the entire surfacepolishing surface 130 may be conditioned. The conditioning head 142 mayhave a further range of motion to move the conditioning head 142 off ofthe platen assembly 202 when not in use.

The conditioning head 142 is adapted to house a conditioning disk 148 tocontact the polishing surface 130. The conditioning disk 148 may becoupled with the conditioning head 142 by passive mechanisms such asmagnets and pneumatic actuators that take advantage of the existing upand down motion of the support arm 144. The conditioning disk 148generally extends beyond the housing of the conditioning head 142 byabout 0.2 mm to about 1 mm in order to contact the polishing surface130. The conditioning disk 148 can be made of nylon, cotton cloth,polymer, or other soft material that will not damage the polishingsurface 130. Alternatively, the conditioning disk 148 may be made of atextured polymer or stainless steel having a roughened surface withdiamond particles adhered thereto or formed therein. The diamondparticles may range in size between about 30 microns to about 100microns.

To facilitate control of the polishing system 100 and processesperformed thereon, a controller 190 comprising a central processing unit(CPU) 192, memory 194, and support circuits 196, is connected to thepolishing system 100. The CPU 192 may be one of any form of computerprocessor that can be used in an industrial setting for controllingvarious drives and pressures. The memory 194 is connected to the CPU192. The memory 194, or computer-readable medium, may be one or more ofreadily available memory such as random access memory (RAM), read onlymemory (ROM), floppy disk, hard disk, or any other form of digitalstorage, local or remote. The support circuits 196 are connected to theCPU 192 for supporting the processor in a conventional manner. Thesecircuits include cache, power supplies, clock circuits, input/outputcircuitry, subsystems, and the like.

FIG. 2 is a partial perspective view of a polishing station 124 of FIG.1 comprising the auto disc changer module 150. FIG. 3 is a top schematicview of the polishing station comprising the auto disk changer module150 of FIG. 2. In one embodiment, as shown in FIG. 1, the auto diskchanger module 150 comprises a disk load/unload station 152 forunloading used conditioning disks from the pad conditioning assembly 140and loading unused conditioning disks onto the pad conditioning assembly140, one or more disk storage stations 154 for storing both used andunused conditioning disks, and a central robot 156 having a range ofmotion sufficient for transferring both used and unused conditioningdisks between the disk load/unload station 152 and the one or more diskstorage stations 154.

FIG. 4 is a side schematic view of a disk load/unload pedestal. In oneembodiment, the disk load/unload station 152 comprises a diskload/unload pedestal 400. In one embodiment, the disk load/unloadpedestal 400 may be coupled directly with the polishing module 106. Inanother embodiment, the disk load/unload pedestal 400 may coupled with aseparate plate coupled with the polishing module 106.

In one embodiment, the disk load/unload pedestal 400 comprises apedestal body 402, a magnetic element 404 coupled with the pedestal body402, and a lift mechanism 406 for raising and lowering the magneticelement 404. The magnetic element 404 uses magnetic force to detach thepad conditioning disk 148 from the conditioning head 142. In oneembodiment, the magnetic element 404 is an electromagnet coupled withthe lift mechanism 406 of the disk load/unload pedestal 400. Themagnetic element 404 may be selectively energized by the power source180 to create a bias force attracting the conditioning disk 148 to thepedestal body 402. As the magnetic force applied by the magnetic element404 is easily regulated by the power source 180, the contact forcebetween the conditioning disk 148 and the pedestal body 402 may beoptimally tailored for specific routines. Moreover, as the attractionforce between the conditioning disk 148 and the pedestal body 402 may beremoved by interrupting power applied to the magnetic element 404, theconditioning disk 148 may be easily separated from the pedestal body402. Optionally, the polarity of the magnetic force generated by themagnetic element 404 may be reversed to assist removing the conditioningdisk 148 in instances where the conditioning disk 148 has becomemagnetized and/or contains permanent magnetic material. Alternatively,the magnetic element 404 may be a permanent magnet. It is contemplatedthat the magnetic element 404 may be disposed in other positions withinor adjacent to the pedestal body 402.

In one embodiment, the lift mechanism 406 may be a passive z-axis liftmechanism. In one embodiment, the lift mechanism 406 comprises a motorcoupled with a lead screw that moves a drive nut attached to themagnetic element 404. As the drive nut is urged vertically by therotating lead screw, the magnetic element 404 moves either upward ordownward. Alternatively, the lift mechanism 406 may be any form of avertical actuator for controlling the position of the magnetic element404. The pedestal body 402, the magnetic element 404, and the liftmechanism 406 may comprise process resistant materials such as ceramics,aluminum, steel, nickel, polymers, and the like that are processresistant and are generally free of contaminates such as copper.

With reference to FIG. 2, the auto disk changer module 150 furthercomprises one or more disk storage stations 154 for storing both usedand unused conditioning disks. In one embodiment, the one or more diskstorage stations 154 comprises a disk storage rack 208. The disk storagerack 208 may be coupled directly with the polishing module 106. Inanother embodiment, the disk storage rack 208 may be coupled with aseparate plate coupled with the polishing module 106.

The disk storage rack 208 comprises a plurality of storage shelves 210supported by a frame 220. Although in one aspect, FIG. 2 illustratesfive storage shelves within the disk storage rack 208, it iscontemplated that any number of storage shelves 210 may be used. Eachstorage shelf 210 comprises a conditioning disk support member 212connected by brackets (not shown) to a frame 220. The brackets connectthe edges of the conditioning disk support member 212 to the frame 220and may be coupled with both the frame 220 and conditioning supportmember 212 using adhesives such as pressure sensitive adhesives, ceramicbonding, glue, and the like, or fasteners such as screws, bolts, clips,and the like that are process resistant and are free of contaminatessuch as copper. The frame 220, storage shelves 210, and brackets maycomprise process resistant materials such as ceramics, aluminum, steel,nickel, polymers, and the like that are process resistant and aregenerally free of contaminates such as copper. While the frame 220 andbrackets may be separate items, it is contemplated that the brackets andconditioning disk support members 212 may be integral to the frame 220.

The storage shelves 210 are spaced vertically apart and parallel withinthe disk storage rack 208 to define a plurality of storage spaces. Eachstorage space is adapted to store at least one conditioning disk 148therein supported by each conditioning disk support member 212. Thestorage shelves 210 above and below each conditioning disk 148 establishthe upper and lower boundary of each storage space.

In one embodiment, as shown in FIG. 1, the auto disk changer module 150further comprises a central robot 156 having a range of motionsufficient for transferring both used and unused conditioning disksbetween the disk load/unload station 152 and the one or more diskstorage stations 154. The central robot 156 is adapted to access boththe disk load/unload station 152 and the one or more disk storagestations 154. In one embodiment, the central robot 156 comprises ashuffling robot assembly 260 (see FIG. 2) generally comprising ashuffling robot body 262 coupled with an end effector assembly 264(e.g., the single blade assembly). The shuffling robot assembly 260 maybe a 2-axis robot. In one embodiment, the shuffling robot assembly 260has rotational motion as shown by arrow 266. In one embodiment, therotational motion may be provided by an actuator such as a rotary aircylinder or a motor. In one embodiment, the shuffling robot assembly 260has vertical motion as shown by arrow 268. The shuffling robot assembly260 may comprise a robot base 270 which couples the shuffling robotassembly 260 with the polishing module 106. In another embodiment, therobot base 270 may be coupled with a separate plate coupled with thepolishing module 106.

In one embodiment, the shuffling robot body 262 comprises a tubularmember. The shuffling robot body 262 may comprise process resistantmaterials such as ceramics, aluminum, steel, nickel, polymers, and thelike that are process resistant and are generally free of contaminatessuch as copper.

In one embodiment, the end effector assembly 264 may be movably coupledwith the shuffling robot assembly 260 such that the end effectorassembly 264 may be rotated in either direction in relation to theshuffling robot assembly 260 about an axis perpendicular to theshuffling robot body 262 and extending through the end effector assembly264. In one embodiment, the end effector assembly 264 comprises one ormore blade assemblies which may contain one or more blades comprising aconditioning disk receiving surface adapted to retain a conditioningdisk positioned on the blade (not shown) by use of various retainingmeans such as a suction mechanism or edge gripping members that hold thesubstrate in position on the robot blade. The edge gripping mechanismcan be adapted to grab the edge of the conditioning disk at multiplepoints (e.g., 3 points) to hold and retain the conditioning disk.

In one embodiment, the blade may have two opposing conditioning disksupporting sides. For example, a used conditioning disk may be securedon one conditioning disk supporting side and an unused conditioning diskmay be supported on the other conditioning disk supporting side. In oneembodiment, the blade may have sensors (not shown) detecting theposition of the substrate with respect to the blade as the end effectorassembly 264 is positioned.

FIG. 3 is a top schematic view of the auto disk changer module of FIG.2. In operation, with reference to FIG. 2 and FIG. 3, the padconditioning assembly 140 deposits a used conditioning disk 148 on thedisk load/unload station 152. In another embodiment, where the diskload/unload station 152 comprises a disk load/unload pedestal, the usedconditioning disk may be placed directly on the disk load/unloadpedestal prior to be retrieved by the central robot 156. In oneembodiment, where the conditioning disk 148 is magnetically coupled withthe pad conditioning assembly 140, the magnetic element 404 may beselectively energized by the power source 180 to create a bias forceattracting the conditioning disk 148 to the pedestal body 402. Theconditioning disk 148 may then be retrieved by the central robot 156from the pedestal body 402. In another embodiment, the end effectorassembly 264 of the central robot 156 is positioned over the magneticelement 404 and the magnetic element 404 is selectively energized by thepower source 180 removing the conditioning disk 148 from the padconditioning assembly 140 and attracting the conditioning disk 148 ontothe end effector assembly 264 of the central robot 156.

After coupling the conditioning disk 148 with the end effector assembly264 of the central robot 156, the central robot 156 transfers the usedconditioning disk to the one or more disk storage stations 154 where theused conditioning disk 148 is deposited on an empty storage shelf. Thecentral robot 156 then retrieves an unused conditioning disk from theone or more disk storage stations 154 and transfers the unusedconditioning disk 148 to the disk load/unload station 152. The unusedconditioning disk 148 may then be coupled with the pad conditioningassembly 140 and the polishing and conditioning process may continue.

In one embodiment, where the end effector assembly 264 comprises a bladehaving two conditioning disk supporting sides, an unused conditioningdisk may be retrieved from the one or more disk storage stations 154 andpositioned on one conditioning disk supporting side and transported tothe disk load/unload station 152. At the disk load/unload station 152the blade may rotate such that the empty disk supporting side canretrieve the used conditioning disk. After securing the usedconditioning disk, the blade may rotate such that the unusedconditioning disk is facing the conditioning head 142 of the padconditioning assembly 140 where the unused conditioning disk may beretrieved from the blade.

FIG. 5 is a top schematic view of another embodiment of an auto diskchanger module 150. In another embodiment, as depicted in FIG. 5, theauto disk changer module 150 further comprises an additional shufflingrobot 502 positioned adjacent to the central robot 156 and the one ormore disk storage stations 154. The additional shuffling robot 502 maybe adapted to retrieve conditioning disks from and deliver conditioningdisks to the central robot 156. The additional shuffling robot 502 mayalso be adapted to transfer conditioning disks 148 into and out of theone or more disk storage stations 154. In one embodiment, the centralrobot 156 transfers a used disk to the additional shuffling robot 502.The additional shuffling robot positions the used disk in the one ormore disk storage stations 154 and retrieves an unused conditioning diskfrom the one or more disk storage stations 154. The central robot 156retrieves and transfers the unused conditioning disk to the padconditioning assembly 140. Advantageously, the central robot 156deposits the used conditioning disk and retrieves the unusedconditioning disk from the same position.

FIG. 6 is a top schematic view of another embodiment of an auto diskchanger module 150. The auto disk changer module 150 comprises a useddisk holder 602 and an unused disk holder 604. It should be understoodthat the positions of the used disk holder 602 and the unused diskholder 604 may be reversed. The pad conditioning assembly 140 discards aused disk in the used disk holder 602 and retrieves an unused disk fromthe unused disk holder 604. In one embodiment, the used disk holder 602and the unused disk holder 604 may be adapted to hold a vertical stackof conditioning disks. In one embodiment, the conditioning disk 148 maybe coupled with and decoupled from the pad conditioning assembly 140 byactuators located on the pad conditioning assembly 140 or actuatorslocated on the disk holders 602, 604. In another embodiment, couplingand decoupling of the conditioning disk from the pad conditioningassembly 140 may be accomplished by passive mechanisms taking advantageof the existing up and down motion of the pad conditioning assembly 140.The used disk holder 602 and the unused disk holder 604 advantageouslyprovide a reduced system footprint and reduced system complexity.

FIG. 7 is a top schematic view of another polishing station 124 of achemical mechanical polishing system and FIG. 8 is a side view of a padconditioning assembly 140 of FIG. 7. In one embodiment, the auto diskchange may be accomplished by carrying multiple conditioning disks 700a-c on the pad conditioning assembly 140. In the exemplary embodimentshown in FIG. 7 and FIG. 8, three conditioning disks 700 a-c are shown.Although three conditioning disks 700 a-c are shown, it should beunderstood that any number of conditioning disks may be carried on thepad conditioning assembly 140.

In this embodiment, the pad conditioning head 142 may index betweenconditioning disks to extend the usable life of each conditioning disk.For example, as shown in FIG. 8, the spare conditioning disks 700 b and700 a (not visible in this view) may be raised above the platen and notused until the active conditioning disk 700 b which engages thepolishing surface 130 during conditioning reaches the end of its usablelife. Alternatively, the multiple conditioning disks 700 a-c may becycled in and out at high frequency to average out variations inconditioning disk quality. In another embodiment, the conditioning disksmay be coupled with a cylinder which is coupled with conditioning head142. As the cylinder rotates, a different conditioning disk is movedinto the active position facing the polishing surface 130.

Although the embodiments described herein generally refer toconditioning disks, it should be understood that the embodimentsdescribed herein may be used with conditioning members of any shapeand/or size.

While the foregoing is directed to embodiments described herein, otherand further embodiments of the invention may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

1. An apparatus for replacing a polishing pad conditioning disk in achemical mechanical polishing system, comprising: a disk load/unloadstation for unloading used conditioning disks from a pad conditioningassembly and loading unused conditioning disks onto the pad conditioningassembly; one or more disk storage stations for storing both used andunused conditioning disks; and a central robot having a range of motionsufficient for transferring both used and unused conditioning disksbetween the disk load/unload station and the one or more disk storagestations.
 2. The apparatus of claim 1, wherein the disk load/unloadstation comprises: a pedestal body; a magnetic element coupled with thepedestal body; and a lift mechanism for raising and lowering themagnetic element.
 3. The apparatus of claim 2, wherein the one or moredisk storage stations comprises: a frame; and a plurality of storageshelves supported by the frame, wherein the plurality of storage shelvesare spaced vertically apart and parallel to define a plurality ofconditioning disk storage spaces supported by the frame.
 4. Theapparatus of claim 3, wherein the central robot comprises: a shufflingrobot body; and an end effector assembly coupled with the shufflingrobot body.
 5. The apparatus of claim 4, wherein the end effectorassembly comprises one or more blades comprising a conditioning diskreceiving surface adapted to retain a conditioning disk positioned onthe blade.
 6. The apparatus of claim 5, wherein the one or more bladeshave two opposing conditioning disk supporting sides.
 7. The apparatusof claim 1, further comprising a shuffling robot positioned adjacent tothe central robot and the one or more disk storage stations, wherein theshuffling robot has a range of motion sufficient to retrieveconditioning disks from and deliver conditioning disks to the one ormore disk storage stations.
 8. The apparatus of claim 1, wherein thecentral robot is positioned in between the disk load/unload station andthe one or more disk storage stations.
 9. A system for chemicalmechanical polishing of a substrate, comprising: a platen assembly; apolishing surface supported on the platen assembly; one or morepolishing heads on which substrates are retained while polishing; a padconditioning assembly for dressing the polishing surface by removingpolishing debris and opening the pores of the polishing surface; and anauto disk changer module for replacing a polishing pad conditioningdisk.
 10. The system of claim 9, wherein the auto disk changer modulecomprises: a disk load/unload station for unloading used conditioningdisks from a pad conditioning assembly and loading unused conditioningdisks onto the pad conditioning assembly; one or more disk storagestations for storing both used and unused conditioning disks; and acentral robot for transferring both used and unused conditioning disksbetween the disk load/unload station and the one or more disk storagestations.
 11. The system of claim 9, wherein the disk load/unloadstation comprises: a pedestal body; a magnetic element coupled with thepedestal body; and a lift mechanism for raising and lowering themagnetic element.
 12. The system of claim 11, wherein the one or moredisk storage stations comprises: a frame; and a plurality of storageshelves supported by the frame, wherein the plurality of storage shelvesare spaced vertically apart and parallel to define a plurality ofconditioning disk storage spaces supported by the frame.
 13. The systemof claim 12, wherein the central robot comprises: a shuffling robotbody; and an end effector assembly coupled with the shuffling robotbody.
 14. The system of claim 13, wherein the end effector assemblycomprises one or more blades comprising a conditioning disk receivingsurface adapted to retain a conditioning disk positioned on the blade.15. The system of claim 9, wherein the one or more polishing heads arecoupled to an overhead circular track that allows the one or morepolishing heads to be selectively positioned over the polishing surface.16. The system of claim 10, wherein the pad conditioning assembly,comprises: a support assembly; a conditioning head supported by asupport assembly; a support arm coupling the support assembly with theconditioning head; a conditioning disk coupled with the conditioninghead, wherein the support assembly has sufficient range of motion toposition the conditioning disk in contact with the polishing surface,and is further adapted to provide a relative motion therebetween.
 17. Amethod for replacing a polishing pad conditioning disk in a chemicalmechanical polishing system, comprising: unloading a used conditioningdisk from a pad conditioning assembly at a disk load/unload station;retrieving the used conditioning disk with a central robot; transferringthe used conditioning disk using the central robot from the diskload/unload station to one or more disk storage stations; unloading theused conditioning disk; retrieving an unused conditioning disk from theone or more disk storage stations; transferring the unused conditioningdisk using the central robot to the load/unload station; and loading theunused conditioning disk onto the pad conditioning assembly.
 18. Themethod of claim 17, wherein unloading the used conditioning disk from apad conditioning assembly comprises selectively energizing a magneticelement to create a bias force to remove the conditioning disk from thepad conditioning assembly.
 19. The method of claim 17, wherein theunloading the used conditioning disk, comprises transferring the usedconditioning disk to a shuffling robot, wherein the shuffling robotpositions the used disk in the one or more disk storage stations. 20.The method of claim 19, wherein retrieving an unused conditioning diskfrom the one or more disk storage stations comprises retrieving anunused conditioning disk from the one or more disk storage stationsusing the shuffling robot.